Abstract: A two-stroke internal combustion engine including a cylinder; and a piston movably mounted in the cylinder. The cylinder includes an exhaust port and transfer ports. The transfer ports include a first pair of the transfer ports disposed closer to the exhaust port than a second pair of the transfer ports which are disposed further away from the exhaust port. The first pair of transfer ports are angled relative to each other at a first angle of about 70° to about 85° and the second pair of transfer ports are angled relative to each other at a second angle of about 120° to about 150°. Directional discharge of scavenged air out of the transfer ports 10 establishes a flow path for the scavenged air to minimize losses of the fresh unburned fuel into the exhaust port.

Abstract: A two-stroke internal combustion engine including a cylinder; and a piston movably mounted in the cylinder. The cylinder includes an exhaust port and transfer ports. The transfer ports include a first pair of the transfer ports disposed closer to the exhaust port than a second pair of the transfer ports which are disposed further away from the exhaust port. The first pair of transfer ports are angled relative to each other at a first angle of about 70° to about 85° and the second pair of transfer ports are angled relative to each other at a second angle of about 120° to about 150°. Directional discharge of scavenged air out of the transfer ports 10 establishes a flow path for the scavenged air to minimize losses of the fresh unburned fuel into the exhaust port.

Abstract: A two-stroke internal combustion engine including a cylinder; and a piston movably mounted in the cylinder. The cylinder includes an exhaust port and transfer ports. The transfer ports include a first pair of the transfer ports disposed closer to the exhaust port than a second pair of the transfer ports which are disposed further away from the exhaust port. The first pair of transfer ports are angled relative to each other at a first angle of about 70° to about 85° and the second pair of transfer ports are angled relative to each other at a second angle of about 120° to about 150°. Directional discharge of scavenged air out of the transfer ports establishes a flow path for the scavenged air to minimize losses of fresh unburned fuel into the exhaust port.

Abstract: A two-stroke internal combustion engine including a cylinder; and a piston movably mounted in the cylinder. The cylinder includes an exhaust port and transfer ports. The transfer ports include a first pair of the transfer ports disposed closer to the exhaust port than a second pair of the transfer ports which are disposed further away from the exhaust port. The first pair of transfer ports are angled relative to each other at a first angle of about 70 degrees to about 85 degrees and the second pair of transfer ports are angled relative to each other at a second angle of about 120 degrees to about 150 degrees. Directional discharge of scavenged charge out of the transfer ports establishes a flow path for the scavenged charge to minimize losses of fresh unburned fuel into the exhaust port.

Abstract: A flail head for a vegetation cutter having face-to-face cup shaped central body portions separated by a predetermined distance Symmetrically spaced pivot posts extend between the face-to-face central body portions. A fail blade is pivotably attached to each pivot post. In one embodiment of the flail head, the face-to-face body portions are identical and the pivot posts are formed by mating semi-cylindrical posts formed integrally with each of the central body portions. The flail blades and body portions are made from different plastic materials to prevent the fusion or welding of the flail blades to the posts.

Abstract: A line trimmer head assembly having a central hub and a body including an annular disc extending circumferentially radially outward from the central hub to removably receive the length of a uniform cross-section line. The disc member is provided with a pair of openings on the disc periphery through which a fixed line length is threaded. The interior portion of the disc is provided with at least two retainer clips having a hook shaped member with an incline ramp surface for cooperating with the portion of the line extending between the two openings. The line is held in place by tension which causes the line to travel down the ramp surface.

Abstract: The present invention provides a lawn mower blade spindle assembly which can be easily serviced in the field, which includes a blade height adjustment feature which allows a blade to be replaced or be adjusted without removing the blade spindle bearings. An improved stress loading arrangement is further provided which reduces spindle stress and lessens the opportunity for spindle assembly failure upon catastrophic blade impact with an immovable object such as with a rock.

Abstract: The present invention provides a lawn mower blade spindle assembly which can be easily serviced in the field, which includes a blade height adjustment feature which allows a blade to be replaced or be adjusted without removing the blade spindle bearings. An improved stress loading arrangement is further provided which reduces spindle stress and lessens the opportunity for spindle assembly failure upon catastrophic blade impact with an immovable object such as with a rock.

Abstract: A mower blade suitable for bagging, side discharge and mulching is provided. A laterally upswept outboard cutting portion cuts the grass and sucks the clippings upwardly. The clippings are forced by the combined effects of the upswept outboard cutting portion and an upswept inboard cutting portion into an intermediate cutting portion where they are further comminuted and are then sucked back into both the outboard cutting portion and the inboard cutting portion. These double circulation paths result in excellent comminution and superior hiding of the clippings.

Abstract: A mower blade suitable for bagging, side discharge and mulching is provided. A laterally upswept outboard cutting portion cuts the grass and sucks the clippings upwardly. The clippings are forced by the combined effects of the upswept outboard cutting portion and an upswept inboard cutting portion into an intermediate cutting portion where they are further comminuted and are then sucked back into both the outboard cutting portion and the inboard cutting portion. These double circulation paths result in excellent comminution and superior hiding of the clippings.

Abstract: The air inlet of the carburetor of an internal combustion engine is connected to an opening in an end wall of the housing of a fan for supplying cooling air to the engine. An inwardly inclined lip at the upstream side of the opening and an inwardly sloping surface at the downstream side of the opening deflect dirt or other solid particles in the air inwardly away from the opening so that the air supplied to the carburetor is freed of such particles. The fan housing and carburetor are directly mounted on the crank case of the engine to provide a compact construction.

Abstract: In a filament type trimmer a filament is wound on a storage spool in a rotating housing and exits through an opening in a rim portion of the housing. When the extending portion of the filament is rotating freely, it extends approximately radially from the housing. However, when it hits a relatively stationary object, it is deflected rearwardly so as to extend approximately tangentially from the housing. To avoid high stresses in the exiting portion of the filament, the exit opening is inclined rearwardly so that when the filament is deflected rearwardly by striking an object, it extends in a tangential line off of the spool, thereby avoiding bending stresses at the exit opening.

Abstract: Disclosed herein is a control for the throttle valve and clutch of an engine, including a timer plate which is oscillated to concurrently adjust the spark and the setting of the throttle valve and a shift lever for shifting the engine clutch. The control includes a shift interlock which is connected to the shift lever for movement in response to movement of the shift lever and a radially outwardly extending projection on the timer plate. The shift interlock includes a portion which is located to extend into the travel path of the timer plate projection and is engageable with the timer plate projection for selectively controlling the setting of the throttle valve in accordance to the position of the shift lever and for selectively controlling the position of the shift lever in accordance with the setting of the throttle valve. A spring member formed as an integral part of the shift interlock releasably engages a detent pin to positively retain the shift lever in any one of its positions.

Abstract: A filament-type trimmer comprises at least one filament spool carried by a rotary housing driven by a motor the speed of which increases with decrease in load. Means for normally restraining rotation of the filament spool relative to the casing is responsive to centrifugal force to release the spool to feed additional filament when the speed of the motor increases due to a decrease in load by reason of the extending end of the filament having become shorter by wearing or breaking off. In one embodiment the feed of additional filament is delayed until by manual control the speed is reduced below normal operating speed.

Abstract: Disclosed herein is a rotary piston engine comprising a housing assembly including a trochoid housing and a pair of end housings aligned and secured together to define a trochoid cavity, a shaft rotatably supported in the end housings and having an eccentric portion disposed in the trochoid cavity, a rotary piston rotatably supported on the eccentric portion of the shaft and extending within the trochoid cavity, the rotary piston having an internal timing gear, a stationary gear separate from the end housings and in mesh with the internal timing gear, a female member extending integrally from one of the end housings and being disposed adjacent to the trochoid housing, the female member having a registering surface in predetermined fixed relation relative to the end housing, and a male member extending integrally from the stationary gear, the male member being pressed into the female member and held in non-rotatable relation by the registering surface.

Abstract: Disclosed herein is a marine propulsion device which comprises an engine having an exhaust port for discharging exhaust gas, and which also comprises a lower unit having an exhaust tube in communication with the exhaust port. The lower unit includes a cavitation plate submerged in water during idle engine operation, and an exhaust outlet in communication with the exhaust tube. The exhaust outlet affords discharge of the exhaust gas below the cavitation plate. The lower unit includes an outer wall including an outlet, which outer wall outlet is located above the cavitation plate and submerged in water during idle engine operation. The lower unit also incudes a passage in communication with the exhaust tube and the outer wall outlet. The passage affords, during reverse engine operation, discharge of a portion of the exhaust gas from the exhaust tube out the outer wall outlet.

Abstract: Disclosed herein is an engine block including first wall portions defining a combustion chamber, second wall portions defining a bore including a first portion extending from the combustion chamber and a second portion enlarged with respect to the first portion, third wall portions defining a water jacket in cooling relation to the second wall portions, and an elongated duct of heat resistant material communicating through the first bore portion with the combustion chamber so as to receive exhaust gases discharged therefrom, which duct is circumferentially engaged by and supported from the second wall portion at locations spaced lengthwise of the duct and extends in the enlarged bore portion in spaced relation from the second wall portions intermediate the locations, whereby there is provided a stagnant air space between the duct and the block intermediate the locations so as to reduce heat transmission from the duct.